Gyroscopic navigational apparatus



Feb. 20, l923.

E. A. SPERRY GYROSCOPIC NAVIGATIONL APPARzL-'IPUS Filed sept. 1s, 1919 INVENTOR [LME/s fl. EPE/mx ATTORNE y l a Patented Feb. Ztl, l923.

nirf tras Miglio ELMER A.. SPELER/Y, GF BROOKLYN, FEW YORK, ASSG-NGR TO THE SPERBIYGYROSCOPE COMPANY, OFBBOOKLYN, NEW YORK, A CORPORATN OF NEN GYROSCOPIC NAY'IGATEONAL APPARATUS.

Continuation of application To all whom t may concern.'

le it known that l, Einem il. Srnnn, a citizen of the United Stateso't America, reH sidingl at 1505 Albemarle Road, Brooklyn, New York, in the countyot liings and State ot' New York, have invented certain new and useful improvements in Gyioscopic Navigational Apparatus, oit which the lol-r lowing is a specification.v

llhis invention relates to gyroscopic appa-l ratus adapted' for navigational purposes in which one or more gyroscopes areeinplo fed to furnish the niariner with his bearings. rllhis application is a division oit n'iy cependingg application for Letters Patent Serial No. 871,885, iiled November 15, 1914, for Navigational apparatus, now matured into Letters Patent No. 1,360,694, November 330, 1920,. and also contains matter divided from iny copending applicationSeria-l No. 47,550,iiled#August 26, 19157 .tor Gyroscopic apparatus for torpedoes.`

r[he present invention is designed tor use as a conipass'bnt vdiffers somewhat 'troni the ordinary gyroscopic compass inthat the instrunient, accordingfto the present invention, possesses no positive directive power but is designed to maintain the direction in which it is set with respect to the earth. it differs, however, troni known instruments ot thisl character in that iny gyroscopic apparatus will followthe rotation ol the earth and, therefore, is desi led to remain horizontal. There are inai y *features of the invention,` however, i of broader applicationA than to this particular embodiment, having' application to gyroscopic'cornpasses and, in

tact. to all ttor-nis of rfvroscooic al oaratus in.) L

used for maintaining a reference plane on moving; bodies, ln fact itis 'just as important, ii not of greater importa-nce, to eliminate disturbing' influences in g'roscopic'apparatus of this character than in ,fyroscopic coinpasses since lin the latter'thei directive torce of the compass will cause it to turnk to the meridian even it temporarily dise placed, while in' this apparatus any displace-v inent becomes permanent and, inore objectionable.,

The purpose or `the present invention is. therefore, "to eliminate sources of deviation from a predetermined plane in vgyro-naifigational apparatus when placed on'inoving; bodies such as ships, whether the' apparatus be ot the n'ieridian seeking type or oit' the hereiiore,

Serial No. 871,885, iled. November 13, d.914.

' 18, 1919. Serial No. 324,731.

This application filed September angles to the plane of the rotor, or in the so-v called inter-cardinal planes. f Friction about the vertical anis necessarily gives rise to precession of the gyroscopes about their hori- Zontal axes. By bringing` into action means responsive to this precessionv and operating about the vertical axis l ain enabled to largely overcome the elfect oi" such friction. lllithont going into? the theory olf the causes oi deviation due to oscillations in the aforementioned plancs the. fact is that such deviations yexist and that by damping` out or preventing` such oscillations it necessarily follows that deviation is prevented 'from this cause.

Referring;` to the drawings in which what l now consider to be the preferred forni of: in v invention is shown 1 is tront elevation, partly in section, of a gyroscopic apparatus manufactured according` to my invention.

Fig. 9j is a side elevation, partly in section, oi" the saine.

Fig. 3 is an enlarged detail of the Contact portions of the gyroscopic apparatusl Fig. 4 is a wirin diagram showing how the motor is actuated from the contacts.

Figs. 5 and 6- are,4 respectively. details showing, inodiiied forms of the trolley contact and the 'contact device for operating; motor 17 'on the instrument.

The main portion of the instrninei'it' com prises two gyroscopic rotors designed to be oppositely-'rotated at the saine speed by polyphase alternating current, similar to the lmethod shown in niv' Patent 1.186.856 ftyroseopic' appstratus7 J une 113, 1916. The rotors are not shown, but are enclosed in close-fitting, air-tight frames or casinos l and 2. which contorni in a general tothe shape ot the rotor. T he rotors inonnted `on horizontal spinningaxes 3 and 4 within the casinga These casinas are pivoted ondiametrically extending, horizontal pivots 4 and '5 on an element or traine (i, which is suspended by means oi a inernber 2' of more or less flexibility. That is, it may be in the forin of a torsion filament or wire desi'ffned to transmit a torque' troni the supporting` spindleS, but to do so gradually and without shock, or it .may bea slender but comparatively stiff rod. As shown, the spindle or support 8 is rotatably supported by a spider 9, which in turn is supported by the usual gimbal rings 10 and 11. Within main frame 12, the support for which is not shown. Secured to said spindle are the large gear 13 and the outer ring 15. Gear 13 supports the compass scale 16 and is designed to be rotated by a motor 17 and to rotate a transmitter 18 for transmitting the readings of the instruments to distant points.

The two casings are preferably superimposed within the frame and symmetrically located with respect to the vertical axis so that no motion of translation is imparted to the gyroscopes when the frame 6 is turned or oscillated in azimuth, and are connected so that precession is permitted only in opposite directions, as by means of segmental gears 18 and 15). By this'simple construction I am enabled to overcome the chief difficulty connected with this type of gyro ap paratus, namely the error arising fron'i the earths rotation, since any tendency for tbe axis of one gyro to rise is opposed bythe equal and opposite tendency of the other gyro. I also employ novel means to overcome the errors due to friction about the vertical axis of the support and due to the force required to drive the transmitter 18, thereby preventing the gyros from wandering. This comprises a contact device which is closed as soon as either gyro precesses beyond a predetermined point, and which operates the motor 17 referred to above. This device may be located upon one of the gears 18 or 19 and upon a bracket 20 fixed to frame 6. It is shown as comprising a trolley 21 pivotally mounted on a base secured to gear 18 and a curved contact strip 24 on bracket 20. Said strip is composed of two conducting sections 25 and 26 separated by a dead section 27. The trolley normally rests on the dead section but a relative inclination in either direction with respect to the frame will cause a circuit to be completed through motor 17, as shown in Fig. 4. This Will exert a torque about the vertical axis through the resilient torsion connection 7 causing the gyro to precess back to its central position. It should be noted that the Contact is so located that it is closed only by relative inclination of the gyros and frame and cannot be closed by swinging of the whole frame 6. The contact device is preferably duplicated on the gyro 2, as shown, corresponding parts being numbered with the samel numerals primed., whereby a more perfect balance and greater reliability are secured and the error due to backlash of the gear teeth overcome.

In order to prevent the element 1b from twisting too far away from the frame 6, due to the resiliency of support 7 under inluence of the motor 17, a limit stop may be employed such as pin 28 on one frame working in a slot 29 in the other. The compass card 16, which is mounted on element 15, will thus be kept in the correct position.

By employing this novel device I eliminate the effect of friction about the vertical axis, since when the ship turns practically the entire work necessary to hold the gyros fixed in space and to rotate the transmitter is performed by motor 17. Said motor may be a standard D. C. motor of any type. As shown, it is provided with two opposed field Windings 30 and 31 connected to the contact strips 25, 26, 25, and 26', as shown in Fig. 4l., so that the motor is reversed every time the trolleys cross from one contact to the other.

In all gyroscopic apparatus which is designed to maintain a level on the surface of the earth, it has been found desirable to provide the apparatus with an eccentric weight designed to'cause precession about the vertical aXis of the instrument at exactly the required rate to keep the instrument in a given position. This rate of precession varies from 360O in 24 hours in a clockwise direction at the north pole through zero at the equator to 360C in' 24 hours in a counter clockwise direction at the south pole. take care of these varying conditions I have devised the adjustable Weight 32 supported from the clamp-pivot 33, and balanced when in its vertical position by a counter weight 4. Hence this position is the correct one for the equator. In north latitude the bob 32 is swung out and adjusted so that it points to the corresponding graduation on the circular' scale 35, while in south latitude it is swung in. My device possesses the further advantage that the scale need not be graduated with a special scale, but is simply laid out in degrees. This feature is due to tbe fact that the moment of the weight required is proportional to the cosine of the latitude, while my device secured this result by providing a circular means of adjustment which, while it is moved through an equal arc for each degree of change in latitude, the moment applied is proportional to the cosine of the angle it makes with its normal eosition.

I prefer also to equip this instrument with means to stabilize or damp out oscillations of the gyroscopes and their supporting means in tbe plane of' the frames 6 and 15, the stabilizing effect ofthe main gyroscopes being suflicient to stabilize the parts in the other planes. For this purpose I employ an auxiliary gyroscope 36 comprising a rotor supported in a casino` 37, which in turn is pivoted on vertical pivots 38 and 38 within a ring 39, the whole being connected to the bottom of the` frame 6 by extension 40 which is jeurnalled in outer or follow-'11p support 15, thereby also forming a lower guide bearing for the trame 6 in support 15. Said gyroscope is also provided with a centralizing spring 41 extending between ring 39 and a point on the gyro casing 3T so that the stabilizing gyroscope will normally be mailitained with its spinning axis 42 at right angles to thel spinning axes 3 and 4 of the main gyroscope and will act to stabilize the frame about an axis perpendicular to the spinning axis 42, in other words, about an axis parallel to the axes of stabilization` oi. the main gyroscope.

lWhile I am aware that it is old to provide an auxiliary gyroscope on gyroscopic apparatus of this general nature, by mounting the stabilizing' gyroscope for independent precession with respect tothe parts to be stabilizedI am enabled to employ a much smaller' stabilizing gyroscope than would otherwise be nec ssary. By means of this gyroscope oscillation in intercardinal planes is largely prevented, and, therefore, deviation due to such oscillation eliminated. The peculiar inter-relation between the directive and stabilizing gyroscope might be pointed out in this connection. The stabilizing gyroscope by preventing or reducing the oscillation of the main frame reduces deviations of the apparatus by eliminating the causes oi error, while the directive gyroscope on the other hand increases the elticiency ot'` the stabilizing gyroscope by preventing turning in azimuth of the main supporting trame 6 when the ship turns. It the stabilizinggyroscope were mounted in a cardon support independent of the directive gyroscope so that it turned with the ship it will at once be apparent that whenever the ship turns a torque would be applied about the vertical axis of the stabilizing gyroscope through the spring 38 thereby causing the stabilizing gyroscope to cause an oscillation of the main trame. If the stabilizing gyroscope is, however, stabilized in azimuth, or in other words, prevented from turning about the vertical axis with the turning of the ship it will prevent oscillation of the pendulous frame almost entirely.

In Fig. 5 a modified form of trolley contact is shown, in which the insulated section 27' is made with a depressed portion 50 so that when the trolley runs on said section, it will exert a centralizing eect on the gyroscopes due to the tension of the trolley spring 51.

Fig. 6.-shows a modified 'form of contact device for oper .tingvthe motor 17 o n the instrument. According to this modification I mount contact strips 25a, 26e, 25", and 26" directly on a portion ot each rotor casing, preferably onv the gear sectors 18 and 19, the strips being separated as before by in-v sulating pieces 27a and 27". vThese strips areplaced on the pitch circle et the gear teeth, being arranged to roll upon each other as indicated, and are insulated from the gears by insulation 45. This arrangement does awaywith the use of any extra parts such as brackets 20 and 20 on the frame 6. It also emphasizes an important advantage of my invention over prior structures, which lies in the factthat the contacts governing motor 17 cannot be closed by any motions of the iframe 6, but only precession ofthe gyroscopes about their pivots 4 and 5.

In accordance with the provisions of the patent statutes, I have herein described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means. Also, while it is designed to use the various :features and elements in the combination and relations described, some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having described my invention, what .I claim and desire to secure by Letters Patent is:

1. In gyroscopic navigational apparatus.y the combination with a support', of a gyroscopic unit which together with its contained parts is pendulously mounted thereon, said unit-comprising a main gyroscope adapted to spin about a normally horizontal axis and mounted for turning in azimuth, an auxiliary gyroscope, and means for mounting' the same on said pendulous unit for independent precession and for spinning about axes at angles to said horizontal 2. In gyroscopic navigational apparatus, the combination with a support, of a gyroscopic unit which together with its contained parts is pendulously mounted thereon, said unit comprising a main gyroscope adapted to spin about a normally horizontal axis and mounted for turning in azimuth, an auxiliary gyroscope, and means for mounting the same on said pendulous unit forprecession about a vertical axis within the said unit.

3. In gyros'copic navigational apparatus, the combination with a support. of a gyroscopie unit which together with its contained parts is pendnlously mounted thereon, said unit comprising a main gyroscope vadapted to spin about a normally horizontal axis and mounted for turning in azimuth. an auxiliary gyroscope, and` means for mountingt-he same for precession about a vertical axis within said unit and for spinning about a vsecond horizontal axis.

4. In gyroscopic navigational apparatus.

the combination with a support, ot a gyroscopi(l unit `which together with its contained parts is pendulously mounted thereon, said unit comprising a main gyroscoliie adapted to spin about a normally horizontal axis and mounted for turning in azimuth, an auxiliary gyroscope, means for mounting' the same on said unit ior independent procession and for spinningyabout axes at angles to said horizontal axis, and resilient means between said gyroscope and unit for centralizing said auxiliary gyroscope about its procession axis.

A gyroscopic navigational instrument comprising a pair ot rotors adapted to be oppositely rotated, iframes for said rotors pivoted upon nori'i'ially horizontal parallel axes and geared together for opposite precession, and an adjustable `Weight for exerting a torque about said horizontal axes.

o. A, gyroscopic navigational. instrument comprising a pair ot rotors adapted to be oppositeiy rotated, trames tor said rotors pivoted upon normally horizontal parallel axes and geared together for opposite precession, an adjustable weight lor exerting a torque about said horizontal axes, and a centralizing means for said trames.

7. ln gyroscopic. apparatus, a trame pivotally supported on a vertical axis, a pair ot oppositely rotated gyros pivotally supported on horizontal parallel axes by said iframe, and connected for opposite precession, and means to prevent said gyros from wandering comprising a motor adapted to exert a torque about said vertical axis.

8. ln gyroscopic apparatus, a frame pivotally mounted about the vertical axis, a pair o'l gyroscopcs supported by said :trame on parallel horizontal axes, and means responsive to relative Vini-cession oit said gyrus about 'd axes tor exerting a torque about said vertical axis.

il. ln. gyroscopic apparatus, a trame pivotally mounted about the vertical axis, a pair oit gyroscopes supported by said :trame on parallel horizontal axes, means connecting said gyroscopcs allowing only relative precession, and means responsive to relative precession ot said gyros about said axes for exerting a torque about said vertical axis.

it). In a gyroscopic navigational instrument, the combinationv 'with a rotor frame pivotally mounted on a horizontal axis, 'of a pi votally mounted adjustable Weight secured to one side oi the trame, a circular scale adapted to be read in connection with said weight, said traine being so designed that by setting the Weightv on the degree on the sca-lc. that is the same as the latitude, the direction and magnitude of the torque exerted by the Weight will cause the instrument to be apparently unailected by the earths rotation.

11. In gym-navigational apparatus, a pendulously supported frame, a gyroscope for stabilizing the same and its connected parts about an axis, a main gyroscope, means it'or mounting the same for oscillation about a second axis and tor turning in azimuth, and means responsive to relative inclination of said main gyroscope and said :trame for exerting a torque thereon.

12. .ln gyro-navigational apparatus, the combination with a gyro-rotor and rotorbearing casing, a pendulous frame on which the said casing is mounted for oscillation about a horizontal axis, a rotatable support for said trame, and means responsive to inclination oit the gyroscope with respect to said trame and support for turning the latter in azimuth.

13. ln gym-navigational apparatus, the combination with a gyro-rotor and rotorbearing casing, a pendulous trame on which the said casing is mounted for oscillation about a horizontal axis, a rotatable support for said iframe, an auxiliary stabilizing gyroscope connected to said frame and support, and means responsive to inclination oit' the gyroscope with respect to said frame and support for turning the latter in azimuth.

14. ln gym-navigational apparatus, the combination With a gyro-rotor and rotorbearing.;- casing, a pendulous frame on which the said casing is mounted for oscillation about a horizontal axis, a follow-up support for said trame, a yielding connection between said support and frame, and means responsive to inclination of the gyroscope with respect to said i'rame and support for turning the latter. y

15. In gym-navigational apparatus, tho combination with a gyIo-rotor and rotorbearing casing, a pendulous frame on which the .aid casing is mounted for oscillation about a horizontal axis, a follow-up support for said frame, an auxiliary stabilizing gyroscope connected to said frame and support, a yielding connection between said support and irame, and means responsive to inclination oi the gyroscope. With respect to said frame and support for turning the latter in azimuth,

16. In gym-navigational apparatus adapted to be carried on a rocking platform, the combination With a gyroscopic directive element including a trame adapted to turn about a vertical axis, a pendulous supporting means ilor said element and frame, means mounting said supporting means for oscillation about a horizontal axis, and gyroscopic stabilizing means mounted on said supporting means adapted to reduce deviation due to motions of said platform.

17. A. gym-.navigational apparatus as claimed in claim 16 in which means are employed to reduce errors due to friction While said supporting means is moving around Said vertical axis. v y

18. In gym-navigational apparatus adapted to be carriedon shipboard, the combinatrame and connected for opposite preccs` ingresos tion with a gyroscopic directive element provided With horizontal pivots, pendulous supporting means therefor, adapted to rotate around a vertical axis, means adapted to compensate for Jfriction While said supporting means is so moving, and stabilizing means connected With said supporting means adapted to reduce deviation due to motions ot said platform.

19. A. gyroscopic-navigational apparatus as claimed in claim 18 in which the said stabilizing means comprises an auxiliary gyroscope mounted' for independent precession and yieldingly connected to said supporting means.

20. In gyroscopic apparatus, a pair ot gyroscopes pivotally mounted in a common sion, electrical contact for saidgyros comprising a pair of contacting strips separated by a block of insulation and a trolley adapted to close an electric circuit on precession of the gyro avvay from the central position, a motor in said circuit connected so as to exert a torque on said frame about an axis at right angles to the precession axis, said block and trolley being designed to exert a centralizing torque about the precession axis as the trolley rolls from a strip onto the block.

2l. In gyroscopic apparatus, a traine pivotally mounted about the vertical axis, a pair of gyroscopes supported by said trame on horizontal parallel axes, resilient centralizing mea-ns for exerting a torque about said horizontal axes on relative precession, and independent means responsive to relative precession of said gyros about said horizontal axes :tor exerting a torque about said vertical axis.

22. In gyroscopic navigational apparatus, a :trame mounted for turning about a vertical axis, an exterior or supporting frame universally mounted for oscillation about horizontal axes, a directive gyroscope pivV oted Within said iirst frame on a horizontal axis, and an auxiliary gyroscope connected to the frames for independent precession to stabilize the same about at least one ot said horizontal axes of oscillation.

9,3. In gym-navigational apparatus, a pair of superimposed gyroscopes, a common frame in Which each is mounted on a substantially horizontal parallel axis, and means mounting said trame for turning about a vertical axis.

E24.v In gyronavigational apparatus, a pair ot superimposed gyroscopes, a common frame in which they are mounted on parallel axes, a support tor said frame rotatablev about a vertical axis and power means for rotating the same controlled by a gyroscope.

25. In gym-navigational apparatus, a` pair Y ot' oppositely acting superimposed gyroscopes, a common frame in Which they are mounted ior oscillation about horizontal parallel axes, means connecting` said gyro` scopes, and means mounting said traine for turning about a vertical axis.

26. In gyroscopic apparatus, a frame .pixV` otally supported on a. vertical axis, a pair oi' oppositely rotated gyroscopes .pivot-ally supported on horizontal parallell axes Within 4said Jframe and connected about said horizontal axes, and means responsive to turning of at least one of said gyroscopes with repect to the 'frame Jr'or exerting a torque thereon about its vertical axis.

27. In gyroscopic navigational apparatus, a support rotatably mounted about a vertical axis, poWer means for rotating the same, a pair orn superimposed oppositely rotated gyroscopes mounted Within said support on substantially parallel axes, and means controlled bv at least one of said gyn roscopes for actuating said power means.

28. In a. gyro navigational apparatus, a pair ot' superimposed oppositely acting gyroscopes, a common trame in Which each is mounted on a substantially horizontal parallel axis, and means for mounting said frame lor turning in azimuth.

29. In a gyro navigational apparatus, a pair ot superimposed oppositely rotating, oppositely acting gyroscopes, a common frame in which each is mounted on a substantially horizontal parallel axis, nand means for mounting said frame for turning in. azimuth. y

30. In gyroscopic navigational apparatus, the combination with a gimbal support, an outer follow-up trame journaled therein for turning about a vertical axis, a sensitive element within said frame including a main gyroscope, and an auxiliary gyroscope connected to'said trame to stabilize said trame and gimbal support.

3l. In gyroscopic navigational apparatus, the combination with a gimbal support, an outer follow-up frame journaled therein for turning about a vertical axis, a sensitive element Within said traine including a main gyroscope and a vertical ring supporting the same on a substantially horizontal axis, and an auxiliary gyroscope connected to said frame to stabilize said trame and gimbal support.

3Q. In gyroscopic apparatus for ships, in combination, a iframe mounted for oscilla- 'ion about a horizontal axis, a gyroscope for stabilizing said trame about said axis, means revoluble about a vertical axis for supporting said gyroscope Within said trame, and a second gyroscope Jfor stabilizing said means and first gyroscope in azimuth.

In combination, a supporting frame mounted for oscillation about a horizontal axis and turning about a vertical axis, a stabil izing gyroscope for stabilizing said frame about said horizontal axis, mea-ns for mountllt) ing said `Uroscope on said frame for freedom about a vertical exis and :i second gyrosoope mounted on said frame for preventing turning of the sume about its vertical axis.

34. In combination, :i supporting frame mounted for oscillation about u. horizontal axis and turning about :i vertical axis, a stabilizing gg'yrosoope for stabilizing said frame about said horizontal axis, means ior mountin g said gyroscope on said frame for freedom 10 about u vertical axis, :i yielding nieuns oonneoting seid gyroscope und said frame about said vertical axis and. a second gyi'oscope mounted on said frame for preventing turning' oi the same about its vertical axis.

In testimony whereof I have affixed nxy signature.

ELMER A. SPERRY. 

